listmonk
Open-source, self-hostable newsletter and mailing list manager — a single Go binary
listmonk is a free, open-source, self-hosted newsletter and mailing list manager — AGPL-3.0-licensed, written in Go, and shipped as a single binary with 21,785 GitHub stars as of June 2026. It gives a founder their own email-sending platform: subscriber lists, SQL-based segmentation, campaign templates, a transactional-message API, and open/click analytics, all on infrastructure you control instead of a per-subscriber SaaS bill. But listmonk is the delivery engine, not the content engine — it sends whatever you write to the lists you build. The harder half of email growth is upstream of the send button: the newsletter people actually want, and the list of the right people to send it to.
What listmonk is
listmonk (github.com/knadh/listmonk) is an open-source, self-hosted application for running newsletters and mailing lists. It sits in the same category as Mailchimp, ConvertKit, or Sendy, with one defining difference: it is AGPL-3.0-licensed and you host it yourself, so your subscriber data and sending reputation stay on infrastructure you own. It is written in Go, backed by PostgreSQL, ships as a single self-contained binary (or a Docker image), and is built to push high volumes of email through your own SMTP provider — so the cost scales with your server, not with a per-subscriber price tier.
- Your own sending platform — subscriber lists, single or double opt-in, and import/export, self-hosted from one binary.
- SQL-based segmentation — target subscribers with real queries against their attributes, not just basic tags.
- Campaigns + templates — compose HTML or plain-text emails with reusable templates and per-campaign analytics.
- A transactional messaging API — fire one-off emails (receipts, confirmations) through the same engine.
- Open-source + self-hostable under AGPL-3.0, so the list and the deliverability are yours, not a vendor's.
Where listmonk fits in a founder's growth stack
listmonk is the delivery layer for owned audience. Email is the one channel a founder fully controls — no algorithm decides who sees it — and listmonk lets you run it without handing your list to a third party or paying per contact as you grow. For a cost-conscious or privacy-conscious founder, that is a real edge: you can grow a list into the tens of thousands and your bill is a small server plus SMTP costs.
But a sending engine only matters once two things exist: a list of people who want to hear from you, and something worth sending them. An empty list sends to nobody, and a great template around thin content still gets unsubscribes. The growth comes from the work upstream of listmonk — earning subscribers and writing a newsletter people open. See how do I start a newsletter for my startup and the broader playbook in how do I get my first 100 users.
What listmonk doesn't do — and what to pair it with
listmonk does not write your newsletter, grow your subscriber list, plan your sending calendar, or tell you which campaign actually drove signups. Like Dub on attribution and OpenPanel on analytics, it is a focused tool: it delivers the email, it doesn't decide what the email should say or who should get it.
| listmonk handles… | …the growth work that fills it |
|---|---|
| Sending and list management | the lead magnet and channels that earn subscribers in the first place |
| Templates and segmentation | the newsletter content and lifecycle emails worth sending each week |
| Open and click stats | the cold-email and content work that turns a list into customers |
This is where Ceres — the AI Growth Officer (agentceres.com) complements a tool like listmonk. Ceres is a managed AI marketing team: a newsletter specialist drafts the issues, subject lines, and lifecycle sequences, you approve what ships, and listmonk is the engine that delivers them. The tool sends the email; the team helps you decide what to send and to whom — and because email is outbound, every send stays behind a human approval step. For how AI engines factor into discovery, see generative engine optimization.
FAQ
- Is listmonk free?
- Yes — listmonk is free and open-source under the AGPL-3.0 license. There is no paid tier of the software itself; you self-host it and pay only for your own server and whatever SMTP provider (such as Amazon SES, Postmark, or your own mail server) you use to actually deliver the email. That is the main reason cost-conscious founders pick it over per-subscriber SaaS pricing.
- Is listmonk open source?
- Yes — the code is public at github.com/knadh/listmonk under AGPL-3.0 and ships as a single self-contained binary backed by PostgreSQL. Because it is self-hosted, your subscriber list and sending data stay on infrastructure you control rather than a vendor's servers.
- How is listmonk different from Mailchimp or ConvertKit?
- Mailchimp and ConvertKit are hosted services that manage sending for you and charge by the number of subscribers, which gets expensive as a list grows. listmonk is self-hosted and open-source: you run it yourself and connect your own SMTP provider, so the cost scales with your infrastructure instead of your list size, and you own the data. The trade-off is that you handle the setup, deliverability, and maintenance that a hosted tool does for you.
- How do I get subscribers for the newsletter listmonk sends?
- The tool delivers email; subscribers come from the value you offer for signing up. Put a clear reason to subscribe on your site, publish content that ranks for what your buyers search, and convert readers into list members. The playbook is the same as any channel — see what marketing channels should a new SaaS start with and how do I start a newsletter for my startup.
You built it. Now grow it.
Ceres is a managed AI marketing team — specialists draft the SEO, social, and outreach that fill your links, you approve what ships. 14-day free trial, from $19/month.